// A C++ program to implement flood fill algorithm 
#include<iostream> 
using namespace std; 

// Dimentions of paint screen 
#define M 8 
#define N 8 

// A recursive function to replace previous color 'prevC' at '(x, y)' 
// and all surrounding pixels of (x, y) with new color 'newC' and 
void floodFillUtil(int screen[][N], int x, int y, int prevC, int newC) 
{ 
	// Base cases 
	if (x < 0 || x >= M || y < 0 || y >= N) 
		return; 
	if (screen[x][y] != prevC) 
		return; 
	if (screen[x][y] == newC) 
		return; 

	// Replace the color at (x, y) 
	screen[x][y] = newC; 

	// Recur for north, east, south and west 
	floodFillUtil(screen, x+1, y, prevC, newC); 
	floodFillUtil(screen, x-1, y, prevC, newC); 
	floodFillUtil(screen, x, y+1, prevC, newC); 
	floodFillUtil(screen, x, y-1, prevC, newC); 
} 

// It mainly finds the previous color on (x, y) and 
// calls floodFillUtil() 
void floodFill(int screen[][N], int x, int y, int newC) 
{ 
	int prevC = screen[x][y]; 
	floodFillUtil(screen, x, y, prevC, newC); 
} 

// Driver program to test above function 
int main() 
{ 
	int screen[M][N] = {{1, 1, 1, 1, 1, 1, 1, 1}, 
					{1, 1, 1, 1, 1, 1, 0, 0}, 
					{1, 0, 0, 1, 1, 0, 1, 1}, 
					{1, 2, 2, 2, 2, 0, 1, 0}, 
					{1, 1, 1, 2, 2, 0, 1, 0}, 
					{1, 1, 1, 2, 2, 2, 2, 0}, 
					{1, 1, 1, 1, 1, 2, 1, 1}, 
					{1, 1, 1, 1, 1, 2, 2, 1}, 
					}; 
	int x = 4, y = 4, newC = 3; 
	floodFill(screen, x, y, newC); 

	cout << "Updated screen after call to floodFill: \n"; 
	for (int i=0; i<M; i++) 
	{ 
		for (int j=0; j<N; j++) 
		cout << screen[i][j] << " "; 
		cout << endl; 
	} 
} 
